/* * Copyright (c) 2016 Cisco and/or its affiliates. * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at: * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ #include <lisp/lisp-cp/packets.h> #include <lisp/lisp-cp/lisp_cp_messages.h> #include <vnet/udp/udp_packet.h> /* Returns IP ID for the packet */ /* static u16 ip_id = 0; static inline u16 get_IP_ID() { ip_id++; return (ip_id); } */ u16 udp_ip4_checksum (const void *b, u32 len, u8 * src, u8 * dst) { const u16 *buf = b; u16 *ip_src = (u16 *) src; u16 *ip_dst = (u16 *) dst; u32 length = len; u32 sum = 0; while (len > 1) { sum += *buf++; if (sum & 0x80000000) sum = (sum & 0xFFFF) + (sum >> 16); len -= 2; } /* Add the padding if the packet length is odd */ if (len & 1) sum += *((u8 *) buf); /* Add the pseudo-header */ sum += *(ip_src++); sum += *ip_src; sum += *(ip_dst++); sum += *ip_dst; sum += clib_host_to_net_u16 (IP_PROTOCOL_UDP); sum += clib_host_to_net_u16 (length); /* Add the carries */ while (sum >> 16) sum = (sum & 0xFFFF) + (sum >> 16); /* Return the one's complement of sum */ return ((u16) (~sum)); } u16 udp_ip6_checksum (ip6_header_t * ip6, udp_header_t * up, u32 len) { size_t i; register const u16 *sp; u32 sum; union { struct { ip6_address_t ph_src; ip6_address_t ph_dst; u32 ph_len; u8 ph_zero[3]; u8 ph_nxt; } ph; u16 pa[20]; } phu; /* pseudo-header */ clib_memset (&phu, 0, sizeof (phu)); phu.ph.ph_src = ip6->src_address; phu.ph.ph_dst = ip6->dst_address; phu.ph.ph_len = clib_host_to_net_u32 (len); phu.ph.ph_nxt = IP_PROTOCOL_UDP; sum = 0; for (i = 0; i < sizeof (phu.pa) / sizeof (phu.pa[0]); i++) sum += phu.pa[i]; sp = (const u16 *) up; for (i = 0; i < (len & ~1); i += 2) sum += *sp++; if (len & 1) sum += clib_host_to_net_u16 ((*(const u8 *) sp) << 8); while (sum > 0xffff) sum = (sum & 0xffff) + (sum >> 16); sum = ~sum & 0xffff; return (sum); } u16 udp_checksum (udp_header_t * uh, u32 udp_len, void *ih, u8 version) { switch (version) { case AF_IP4: return (udp_ip4_checksum (uh, udp_len, ((ip4_header_t *) ih)->src_address.as_u8, ((ip4_header_t *) ih)->dst_address.as_u8)); case AF_IP6: return (udp_ip6_checksum (ih, uh, udp_len)); default: return ~0; } } void * pkt_push_udp (vlib_main_t * vm, vlib_buffer_t * b, u16 sp, u16 dp) { udp_header_t *uh; u16 udp_len = sizeof (udp_header_t) + vlib_buffer_length_in_chain (vm, b); uh = vlib_buffer_push_uninit (b, sizeof (*uh)); uh->src_port = clib_host_to_net_u16 (sp); uh->dst_port = clib_host_to_net_u16 (dp); uh->length = clib_host_to_net_u16 (udp_len); uh->checksum = 0; return uh; } void * pkt_push_ip (vlib_main_t * vm, vlib_buffer_t * b, ip_address_t * src, ip_address_t * dst, u32 proto, u8 csum_offload) { if (ip_addr_version (src) != ip_addr_version (dst)) { clib_warning ("src %U and dst %U IP have different AFI! Discarding!", format_ip_address, src, format_ip_address, dst); return 0; } switch (ip_addr_version (src)) { case AF_IP4: return vlib_buffer_push_ip4 (vm, b, &ip_addr_v4 (src), &ip_addr_v4 (dst), proto, csum_offload); break; case AF_IP6: return vlib_buffer_push_ip6 (vm, b, &ip_addr_v6 (src), &ip_addr_v6 (dst), proto); break; } return 0; } void * pkt_push_udp_and_ip (vlib_main_t * vm, vlib_buffer_t * b, u16 sp, u16 dp, ip_address_t * sip, ip_address_t * dip, u8 csum_offload) { u16 udpsum; udp_header_t *uh; void *ih; uh = pkt_push_udp (vm, b, sp, dp); if (csum_offload) { ih = pkt_push_ip (vm, b, sip, dip, IP_PROTOCOL_UDP, 1); b->flags |= VNET_BUFFER_F_OFFLOAD_UDP_CKSUM; vnet_buffer (b)->l3_hdr_offset = (u8 *) ih - b->data; vnet_buffer (b)->l4_hdr_offset = (u8 *) uh - b->data; uh->checksum = 0; } else { ih = pkt_push_ip (vm, b, sip, dip, IP_PROTOCOL_UDP, 0); udpsum = udp_checksum (uh, clib_net_to_host_u16 (uh->length), ih, ip_addr_version (sip)); if (udpsum == (u16) ~ 0) { clib_warning ("Failed UDP checksum! Discarding"); return 0; } /* clear flags used for csum since we're not offloading */ b->flags &= ~(VNET_BUFFER_F_IS_IP4 | VNET_BUFFER_F_IS_IP6); uh->checksum = udpsum; } return ih; } void * pkt_push_ecm_hdr (vlib_buffer_t * b) { ecm_hdr_t *h; h = vlib_buffer_push_uninit (b, sizeof (h[0])); clib_memset (h, 0, sizeof (h[0])); h->type = LISP_ENCAP_CONTROL_TYPE; clib_memset (h->reserved2, 0, sizeof (h->reserved2)); return h; } /* *INDENT-ON* */ /* * fd.io coding-style-patch-verification: ON * * Local Variables: * eval: (c-set-style "gnu") * End: */